假道伐虢 [ㄐㄧㄚˇ ㄉㄠˋ ㄈㄚˊ ㄍㄨㄛˊ; jia3 dao4 fa2 guo2] to obtain safe passage to conquer the State of Guo to borrow the resources of an ally to attack a common enemy (idiom) ◄ ►